It is becoming increasingly apparent that non-nicotine stimuli (i.e., smell, taste) play a larger role in smoking maintenance and relapse for women than men. These stimuli may become conditioned reinforcers because of their association with nicotine, and the direct pharmacological effects of nicotine on responding for conditioned reinforcers is poorly understood. Furthermore, female rats are rarely included in laboratory studies of the effects of nicotine on responding maintained by various environmental consequences, therefore studying sex differences to the behavioral effects of nicotine will make a valuable contribution. Two experiments will use the observing response procedure to examine effects of acute and chronic nicotine exposure on responding maintained by primary and conditioned reinforcers, as well as examining changes in general locomotor activity, in male and female Long-Evans rats. Experiment 1 will pair a visual stimulus with food availability, and to extend the generality of this effect Experiment 2 will pair an auditory stimulus with food availability. If nicotine increases responding for conditioned reinforcers to a greater extent in female rats than in male rats, this will provide useful information regarding the gender disparity in the importance of non-nicotine stimuli to smoking maintenance and relapse. [unreadable] [unreadable] [unreadable]